These photos were shot at the Bountiful Landfill in Bountiful Utah on January 12, 2001.  This bird's mantle was slightly darker than the Herring Gulls present and consistent with other Thayer's Gulls present.  In direct comparison, it's legs were indistinguishable in color from Herring Gulls and clearly lighter pink than Thayer's Gulls present.  Primary extension had three A-spots past the tail tip.  Primaries were white with gray markings which appear darker in most of these photos.  Iris was dark, but not as dark as California Gulls and did not appear solidly brown, rather flecked with lighter brown.